Abstract

Background: Attendance in screening is an important determinant of cervical cancer. Previous experience on high-risk human papillomavirus (hrHPV) DNA testing on patient-obtained samples suggests a good effect among non-attendees of screening. We assessed the effects of self-sampling on attendance in the Finnish screening programme.
Methods: Non-attendees after the primary invitation in one municipality (Espoo) were randomised to receive either a self-sampling kit (2,397 women) or an extra invitation (6,302 women). One fourth (1,315 women) of reminder-letter arm non-attendees also received a self-sampling kit as a third intervention. Main outcomes were increases in screening attendance and coverage.
Results: The adjusted relative risk (RR) for participation by self-sampling as a second intervention in comparison to a reminder letter was 1.21 (CI 1.13-1.30). Total attendance increased from 65% to 76% by self-sampling, and from 65% to 74% with a reminder letter. Combining the interventions (reminder letter, then self-sampling) increased total attendance from 63% to 78%. One fifth of the participants in all three groups increased screening coverage (previous Pap-smear ≥5 years ago or never). Self-obtained samples were more often HPV-positive than provider-obtained ones (participants after primary invitation and reminder letter), 12-13% versus 7%.
Conclusions: Self-sampling is a feasible option in enhancing the attendance at organised screening, particularly as an addition to a reminder letter.
Impact: If self-sampling is used as a third intervention after two written invitations, the overall attendance in Finland could most likely reach the desired 80-85%.